Do Protestants and Roman Catholics really believe different things regarding salvation? Watch as R.C. Sproul explains that the gospel itself was at stake in the Reformation.
The Reformers were saying that we are justified by faith and by faith alone—that faith is the sole instrumental cause for our justification meaning that the way we receive all the benefits of Jesus work is through putting our trust in Him and in Him alone. Now in contrast to that, the Roman communion taught as they did at Trent, that faith is a necessary condition for salvation, but you can have that true faith and still not be justified. So you have radically different views of salvation, and those two views cannot be reconciled. One of them is the gospel. One of them is not. And so what was at stake in the Reformation was the gospel of Jesus Christ. And though Rome made many fine affirmations of traditional truths of the Christian faith, by anathematizing the gospel, in my mind, they stopped being a legitimate church.